Electrochemical cells are known making it possible to produce electricity through an oxidation-reduction reaction between an oxidizing fluid and a reducing fluid. In particular, fuel cells are known making it possible to produce electricity through an oxidation-reduction reaction between a fuel, comprising hydrogen, and an oxidizer, comprising oxygen. The fuel is injected into an anode conduit and the oxidizer is injected into a cathode conduit of the cell, an electrolyte layer providing the sealing between these two conduits, while allowing ion exchanges. Due to these ion exchanges, the hydrogen contained in the fuel can react with the oxygen contained in the oxidizer to yield water, while generating electrons in the anode. During the operation of the cell, a difference in potential then follows between the two sides of the electrolyte, this difference in potential being able to be used to create an electric current.
However, the differences in potential established within a fuel cell remain small, around 0.6 to 1.0 V. Consequently, to obtain a usable output voltage, the cells are most often stacked and electrically connected to one another in series, within what is commonly called a fuel cell. The anode conduits of the electrochemical cells are fluidly connected to one another within what forms an anode compartment of the fuel cell, and the cathode conduits of the electrochemical cells are fluidly connected to one another within what forms a cathode compartment of the fuel cell.
To avoid damaging the electrolyte layer of the cells, it is necessary to limit the pressure differential between the anode and cathode compartments. To that end, the fluid pressure in one of the anode and cathode compartments is generally controlled based on the fluid pressure in the other compartment, for example using an expander.
WO 2011/083502 thus discloses a method for controlling a fuel cell in which the fluid pressure in the cathode compartment is kept at a target pressure lower than a threshold pressure depending on the pressure in the anode compartment, to avoid breaking the membranes of the cells.
However, the fluid pressure in the compartment used as a reference to control the fluid pressure in the other compartment increases in an uncontrolled manner. This uncontrolled increase in the fluid pressure of the fuel cell risking damaging it greatly, it is necessary to stop the fuel cell. This results in repeated and uncontrolled mechanical stresses of the membranes of the cells, which may damage them.